Barriers to reducing preoperative testing for low-risk surgical procedures: A qualitative assessment guided by the Theoretical Domains Framework

Introduction While numerous guidelines do not recommend preoperative tests for low risk patients undergoing low risk surgeries, they are often routinely performed. Canadian data suggests preoperative tests (e.g. ECGs and chest x-rays) preceded 17.9%-35.5% of low-risk procedures. Translating guidelines into clinical practice can be challenging and it is important to understand what is driving behaviour when developing interventions to change it. Aim Thus, we completed a theory-based investigation of the perceived barriers and enablers to reducing unnecessary preoperative tests for low-risk surgical procedures in Newfoundland, Canada. Method We used snowball sampling to recruit surgeons, anaesthesiologists, or preoperative clinic nurses. Interviews were conducted by two researchers using an interview guide with 31 questions based on the theoretical domains framework. Data was transcribed and coded into the 14 theoretical domains and then themes were identified for each domain. Results We interviewed 17 surgeons, anaesthesiologists, or preoperative clinic nurses with 1 to 34 years’ experience. Overall, while respondents agreed with the guidelines they described several factors, across seven relevant theoretical domains, that influence whether tests are ordered. The most common included uncertainty about who is responsible for test ordering, inability to access patient records or to consult/communicate with colleagues about ordering decisions and worry about surgery delays/cancellation if tests are not ordered. Other factors included workplace norms that conflicted with guidelines and concerns about missing something serious or litigation. In terms of enablers, respondents believed that clear institutional guidelines including who is responsible for test ordering and information about the risk of missing something serious, supported by improved communication between those involved in the ordering process and periodic evaluation will reduce any unnecessary preoperative testing. Conclusion These findings suggest that both health system and health provider factors need to be addressed in an intervention to reduce pre-operative testing.


Introduction
Preoperative tests (e.g., chest x-rays, electrocardiograms (ECG), and baseline laboratory studies) are performed to provide additional information about high-risk patients (i.e., those with known risk factors identified via clinical history and physical examination) to help anaesthesiologists prepare them for surgery and improve perioperative outcomes [1][2][3]. In practice, however, preoperative testing is often performed using a routine testing strategy, defined by the Agency for Healthcare Research and Quality as tests conducted on all patients undergoing given procedures, regardless of patient history [4]. Without supporting evidence, many hospitals have chosen to implement routine testing as a "fail-safe," seemingly under the impression that more information (from more tests) will increase patient safety and decrease potential legal action resulting from adverse events [2].
The scientific foundation for the use of routine testing is very weak. A Cochrane review published in 2012 found that routine preoperative tests did not reduce the risk of intraoperative or postoperative adverse events when compared with selective or no testing for patients undergoing cataract surgery [5]. Similarly, another review on trials involving cataract surgery and various types of ambulatory procedures concluded that routine preoperative testing did not affect clinical management or reduce total perioperative complications, morbidity or mortality compared with no testing [4,6]. There are few studies on the effects of routine preoperative testing for other types of low-risk surgeries making it difficult to draw conclusions on the utility of routine preoperative testing within these settings [4,7].
Because routine testing lacks evidence to support its use, it is considered low-value care and current clinical practice guidelines and Choosing Wisely recommendations advise against routine preoperative testing for healthy adult patients undergoing low-risk surgical procedures [8][9][10][11][12]. These are procedures for which the combined surgical and patient characteristics predict a low-risk (<1% in American guidelines) of a major adverse cardiac event (such as death or myocardial infarction) [13,14]. In addition to its considerable cost [2,10,15], it is doubtful that any benefits realised using routine testing outweigh the drawbacks (e.g., extra testing, incidental findings that require additional costly investigations, surgical delays and patient stress/ harm) [2]. Unfortunately, routine preoperative testing for low-risk surgeries persists. Between the fiscal years 2011/2012 and 2012/2013, preoperative tests (including ECGs, chest x-rays, stress tests, and transthoracic echocardiograms) preceded 17.9%-35.5% of low-risk procedures across the Canadian provinces of Alberta, Saskatchewan, and Ontario [9]. Additionally, an Ontario study conducted using provincial data from 2008 to 2013 showed that ECGs and chest x-rays were conducted before 30.9% and 10.8% of procedures, respectively [16]. Similar figures have been reported internationally [10,[17][18][19].

Improving uptake of guidelines
Translating guidelines into clinical practice is challenging, and simple guideline dissemination is unlikely to change clinical practice behaviours that are influenced by a multitude of factors [20]. It is important to understand what is driving behaviour when developing interventions to change it [21,22]. Ideally, this process should be guided by a theoretical framework of established psychological theories of behaviour change [20][21][22][23]. The Theoretical Domains Framework (TDF) was developed by Michie et al. to identify factors influencing health professionals' implementation of evidence-based guidelines into practice [24][25][26]. The TDF simplifies 128 constructs from 33 behaviour change theories into 12 theoretical domains [26,27]. Each theoretical domain may be a determinant of the behaviour that requires change.
We are aware of only one Canadian study using a theory-based approach to examine healthcare providers' (HCPs) barriers to de-implementing routine preoperative tests for lowrisk surgeries. [28] Patey et al found the most common barriers identified by anesthesiologists and surgeons practicing in Ontario, Canada were related to the lack of clarity regarding who was responsible for ordering the tests, perceived inability to cancel tests ordered by other HCPs, and tests being ordered and completed prior to the anaesthesiologist's examination of the patient [28]. While some of the drivers of behavior may be similar among HCPs across Canadian provinces, healthcare systems are provincially managed leading to contextual differences in each province. Indeed, even within provinces, practices can vary from hospital to hospital. We completed a TDF-guided investigation of our local context by conducting a series of semi-structured interviews with surgeons, anaesthesiologists, and preoperative clinic nurses in Newfoundland and Labrador (NL) to identify perceived barriers and enablers to reducing unnecessary preoperative tests for low-risk surgical procedures.

Design
This was an exploratory, qualitative study conducted using semi-structured interviews to understand HCPs' barriers and enablers to de-implementing low-value preoperative testing. The protocol for this study was previously published [29]. This study was reported according to the Consolidated criteria for Reporting Qualitative research (COREQ) checklist [30].

Participants
Participants were selected using a purposive snowball sampling strategy in order to ensure diverse perspectives and representation across the four regional health authorities (RHA) in NL, as well as a variety of surgical subspecialties. We identified a key informant within the largest RHA, Eastern Health, to provide a list of three potential participants as well as potential informants from the other three RHAs across the province. At the end of each interview, participants were asked to identify additional participants who may be interested in participating in this study.
Eligible participants were HCPs (surgeons, anaesthesiologists, or preoperative clinic nurses) practising in NL who order preoperative tests for patients undergoing surgery.

Data collection
Potential participants were emailed by a researcher (KM or AH) to gauge their interest in participating in the study. Oral consent was obtained, and semi-structured interviews were conducted by two interviewers (AP and AH, both females, with graduate degrees in the health sciences, and employed as academic faculty and/or researchers). The interviewers were trained in qualitative methods and interview techniques, with over 15 years of experience. Participants learned about the interviewers at the start of the interview via verbal introduction; there was no relationship between the interviewers and participants established prior to the start of the study. Field notes were taken by a non-participant observer (RL or KM) during the interviews as a fail-safe measure in case of a recording failure) but were not used in the analysis. Interviews were conducted over the phone or in-person. All interviews were audio-recorded and transcribed verbatim. No repeat interviews were carried out. Transcripts were not returned to participants for comments and/or corrections and participant checking of findings was not performed.

Interview guide
The behaviour of interest was ordering of preoperative tests (chest x-rays and ECGs) for healthy patients undergoing low-risk surgical procedures (knee arthroscopy, laparoscopic cholecystectomy, cataract removal, and similar types of surgeries). Healthy patients were defined as those without comorbidities or additional medical conditions that could complicate anaesthesia management and perioperative care [28]. The interview guide (adapted from Patey et al.'s study with surgeons and anaesthesiologists on preoperative testing in Ontario [28]) was developed using the TDF to elicit participant beliefs about their behaviour through the lens of each domain. It included 1-4 questions per domain (12 domains), for a total of 31 questions and prompts were provided in the interview guide to assist the interviewer in clarifying participants' responses if needed. No changes were made to the guide after pilot testing with our key informant. Please see the published study protocol for a copy of the interview guide [29].

Data analysis
Following the method outlined in the TDF guide [26], coders read and reread transcripts to become familiar with the data. Coding began after six interviews were completed and transcribed. Using the TDF to generate a framework for content analysis, researchers analyzed the data deductively (assigning text to one or more domains) and inductively (identifying themes within each domain. Deductive analysis. Two coders (SI, SM), trained in TDF coding by an expert in TDF and behavioral sciences (AMP), developed a codebook which served as a guide and reference for the coders to ensure accuracy and consistency. To develop the codebook, one interview was coded in NVivo (V.12, QSR International, Melbourne, Australia) in tandem with access to an expert coder (AMP) for review and correction. A second transcript was coded independently to validate the codebook and calculate interrater reliability using Fleiss's Kappa (κ) [31]. Domains with κ<0.8 (indicating less than 'substantial agreement' or 'excellent agreement' [32]) were reviewed for consensus. Any disagreements amongst the two researchers about coding were reviewed by the TDF expert (AMP). Once the coders were comfortable with their strategy, they continued to independently code the remaining transcripts, reviewing agreement every three interviews to ensure consistency. Again, any domains with κ<0.8 were reviewed and coded to consensus. Please see the published protocol for this study for a copy of the codebook [29].
Inductive analysis. After interview responses were coded into TDF domains, themes were identified for each domain, phrased as belief statements about barriers or enablers to preoperative test ordering. These were further examined to identify broader themes or patterns in the data. All belief statements and broad themes (with supporting quotes) were reviewed by the second coder and AMP.

Identifying relevant domains
Relevant domains were identified through consensus discussion between the two coders (SI, SM), confirmed by AMP, and subsequently reviewed with the larger research team. Relevant domains are those for which sufficient data were coded to inform an intervention for behaviour change [33]. Three factors were considered to identify relevant domains: (1) reported strength of opinion that the beliefs influenced the behaviour, (2) presence of conflicting beliefs, and (3) frequency of the beliefs across interviews [26]. All factors were considered concurrently to establish domain importance.

Ethics
Ethics approval was obtained from the Health Research Ethics Board in Newfoundland and Labrador (HREB #2018.190).

Results
We interviewed seven surgeons, five anesthesiologists and five nurses from hospital (twelve) or hospital and community settings (five) who had practiced between 1 to 34 years (mean ± SD, 14.23 ± 9.33). Data saturation was achieved after 17 interviews. The interviews took between 13 to 76 minutes (mean ± SD, 38.97 ± 14.82). Initial interrater reliability for domains ranged from k = 0 to k = 1 (mean = 0.58 ± SD = 0.22). For Kappas below 0.8, disagreements were discussed in order to reach consensus for all domains.

Preoperative assessment process
Participants reported different definitions of "low-risk surgeries," but generally, both patient characteristics (past medical history and physical exam) and type of the surgery were reported to play a role in defining a surgery as low-risk. Same-day surgeries (i.e., the patients who could go home after the surgeries) and those that did not require general anaesthesia were regarded as low-risk. Some participants considered patients of certain age groups (e.g., 50, 60, 70 years) as high-risk regardless of other factors.
There were inconsistencies among the participants when describing the process for preoperative assessment. Most often, patients were initially seen by surgeons. Based on their medical history, physical exam, and type of required anaesthesia, they were either referred to the preadmission centres (PAC) or were booked directly for their surgery without any preoperative assessment. If patients were referred to a PAC, they would first undergo an assessment by PAC nurses (sometimes this would be done via telephone). The nurses reviewed patients' medical history, discussed the details of the surgery with them, and referred them to in-person visits by anaesthesiologists for further examination and tests (if necessary). However, in some centers, the anaesthesiologists' visits were only required if any red flags were highlighted by the nurses.
Although most participants reported that the tests were ordered at PACs by anaesthesiologists, tests were also ordered at surgeons' offices or by nurses during the telephone interviews. In some rare occasions, especially if patients were admitted as outpatients by surgeons, the anaesthesiologists would not see the patients until the moment of surgery.

Key themes among relevant domains
Theoretical domains identified as relevant to preoperative test ordering were: beliefs about capabilities, beliefs about consequences, social/professional role and identity, motivation and goals, social influences, environmental context and resources, and behavioural regulation. Table 1 presents a summary of the belief statements and supporting quotes for each of the relevant domains.
Four overarching themes are described below 1. While HCPs may not intend to routinely order preoperative tests, in practice, a host of factors play a role in ordering decisions including use of automatic order sets, workplace norms, expectations about the needs and wants of other HCPs, and lack of access to information, technological tools, and human resources. Most participants stated that they did not intend to routinely order tests and were comfortable with the idea of not doing so. However, some believed that the tests are important to carry out to provide the clinical team with as much information about the patient (and potential adverse outcomes) as possible (motivations and goals, beliefs about consequences).
Participants reported a variety of factors that impacted their ordering decisions, some of which were outside of their influence (e.g., institutional use of automatic order sets and 'There's always a little bit of friction between anesthesiology and surgery, and surgery wants to proceed, and anesthesia is happier to cancel. So, in my mind, it was always like let's do everything and that way there's no way they can cancel them.' (S2) 'They (surgeons) do a history and physical as well. It won't be in the same because they're looking for different things, so they won't be reviewing the patient on active cardiac and respiratory symptoms usually they're more just have a story surrounding their surgical problem and then a review of their systems and a past medical history of course.' (A14) 8 Abnormalities or patients I'm not sure about need to be reviewed by anesthesia or internal medicine (Barrier).
'Any patient that we have any question about we ah, we have an understanding amongst our group to refer them either to internal medicine or anesthesia for preoperative workup if necessary, um before ah going ahead with the surgery.' (S16) 'If I do have any questions or concerns after that, I would put the patient for review, and I do ask the anesthetist at that time.' (N9) 7 Anesthesiology doesn't always see test results because they go to the surgeon, whose name the test is under (Barrier).
'So, we (anesthesiologists) want to be informed, but laboratory doesn't inform us directly. Laboratory will inform the surgeon. . .We want to be informed if it's going to affect our ability to give the anesthetic. That doesn't always come through to us.' (A7) 'Is there anything in your professional role as a surgeon that influences your decision to order or not order certain tests for a patient having a low-risk surgery? I wouldn't say so.' (S4)

5
Ordering a CXR or ECG for all patients is not an expected part of my preoperative check (Enabler).
'Is ordering a chest x-ray or ECG for every patient an expected part of the pre-op visit? Not anymore, thankfully.' (S2) 12 Reviewing a CXR or ECG for low-risk patients/ surgeries is not an expected part of my preoperative check (Enabler).
'Is a review of a chest x-ray or echocardiogram an expected part of a pre-op check? I wouldn't say it's an expected part, no.' (S4) 8 Test ordering I'm not in charge of ordering (Barrier). 'So, we don't make that decision, we gather the information and pass it along to the doctor (anesthesiologists).' (N17) 'I'm not the person ordering these tests, I'm kind of a step back from the process.' (A13) 7 Tests happen in surgeons' name without they ordering them personally (Barrier).
'They're asking the patient to do certain things and I might not even know what they have asked. But I am supposed to know because it goes in my name, but then the decision-makers are the nurses and the anesthesiologists and the PAC clinic.' (S3)  'I'm very familiar with the guidelines and the evidence, and it makes me very comfortable in not ordering these things.' (S1) 'You're comfortable proceeding without ordering those kinds of test for a low-risk patient? In a low-risk patient and low-risk procedure? Yes.' (A14) 17 Ease of ordering It is easy for me to order tests (Barrier).
'How easy or difficult is it for you, personally, to order pre-op tests? It would be dead easy if I wanted to.' (S4) 'It's very easy to order the stuff and yeah all your colleagues like the nurses they'll help you get that done for sure whether it's drawing blood, or chest x-ray or EKG or stuff yeah it's not hard to do at all.' (A15) 13 Ease of not ordering or cancelling It's difficult to cancel tests once they've been ordered (Barrier).
'Well if a physician orders something, I've got no right to go against them.' (N12) 'Trying to retract that once the patient disappears from your presence, it's very difficult, to be honest with you. Once you send them off to have something like that done, it tends to get done and you wouldn't have a chance to cancel it.' (S1) 5 Tests are done before I see the patient, I can't cancel or change orders (Barrier).
'By the time we've seen them they've had their investigations done because they see the nurse, they're sent off to get their investigations done and then they come back and see us. So, it's almost always done by the time we see them. So those would be impossible to cancel because they're done.' (A15) 2 It is easy for me not to order tests (Enabler). 'Personally, it is very easy for me not to order a test.' (S1) 'I guess it's fairly easy to order no tests.' (N10) Not ordering is more efficient, cost-effective and avoids wasting of resources (Enabler).
'Long-term, it (not ordering tests) would decrease resource use and resource waste and probably allow easier access to those resources.' (S4) 'We're ordering tests that we don't need alright. However, once they have arrived you know I can't do anything about the tests they've already done and it's a complete and utter waste of money.' (A13) 12 Not ordering reduces wait times for surgeries (Enabler).
'It (not ordering tests) would get people probably to the OR a little faster because they wouldn't be waiting for tests.' (S4) 3 Not ordering tests means less paperwork (Enabler).
'I think the positive thing if we order less things would be just that we have less things coming through our inbox, which is a wonderful thing, especially now with the EMR. Oh my God, it's full all the time of crap that I don't want to see.' (S2) 4 The results of these tests are unlikely to change my practice (Enabler).
'I have to follow up on it even though it was not a test I ordered. And that is absolutely infuriating. Mostly because it may not affect the surgery and the clinic that ordered it to help with the surgery isn't actually following up on their own test results, which is inappropriate.' (S5) 'Testing in general doesn't add much to anesthesia I don't think if you can get a decent history and physical from them there's very little else information that you're getting so. Predicted values are low.' (A15) 10 Reasons for ordering Tests are ordered because of fear of cancelling or delaying the surgery by anesthesia (Barrier).
'The only reason a surgeon would order any of these tests is a fear that the patient would be canceled by anesthesia if these tests were not ordered, or a case would be delayed in some fashion.' (S1) 'But generally speaking, is driven by the surgeon and to some extent what they order is try and keep the anesthetist happy, so they don't get a case cancelled.' (A13) 7 If I'm concerned and not sure, I'll order (Barrier).
'If I was truly worried I would just order it right and I think I'm you know confident enough to that and some of my colleagues I think for the majority would be fine just saying so but I'm just going to order so.' (A15) 4 I sometimes order tests to avoid conflicts with other colleagues (Barrier).
'When it comes to the patient getting affected because I am in conflict with another provider, a certain test which I don't think it is necessary and the other person thinks vice versa, then I don't have much say in cancelling it and I will go ahead, because at the end of the day, I would have to think that will benefit the patient.' (S3) 3 Sometimes, tests are ordered to avoid legal issues (Barrier). 'Overall would you say that the positive consequences of not ordering um outweigh the negatives or the other way around? No, I for sure would say that they outweigh the negatives.' (S16) 9 Lots of testing we do is unnecessary (Enabler). 'In order to not miss a few percentages of patients, 90 per cent of patient are having unnecessary investigations.' (S3) 3 There is no benefit to routine testing for all patients (Enabler).
'The idea of blanket ordering isn't well established or isn't a great practice.' (A14) 3 (Continued ) 'We've tried to remove order sets within the hospital, but I can tell you they still exist and they still float around and some of them will have the special needs CBC, da, da, duh and they'll have a whole string of tests that theoretically you're supposed to think about before you tick them.' (A7) 5 Difficulty in accessing other specialists and consulting with them causes unnecessary test ordering (Barrier).
'Now I've found something in pre-admission, we don't have any setup, especially at [hospital], I want another opinion or I want an internist or I want a cardiologist to look at it. . .It's very difficult to get someone to see them so therefore, that will turn me around and I will probably investigate more. . .then I may tend to order more tests on them, than probably necessary that if the specialist in that area is seeing anybody, say okay, you don't have to do this.' (A8) Any nuances of symptoms then, we feel we have to investigate before going ahead. But if this was documented beforehand, then I wouldn't worry about it and I wouldn't go on any investigations in pre-admission so it wouldn't make a difference. . .some of those processes, probably if at the surgeon's time of referral and they're doing their assessment, if at least the assessment was documented completely and fully with the results, that might be better rather than just there's no ordering of tests necessary.' (A8) 1 Face-to-face pre-admission assessments, instead of phone interviews, can help in decreasing testing.
I just think that sometimes maybe things wouldn't get ordered if I was doing it face-to-face. Maybe more things would be getting ordered if I did it face to face, but I don't know if that will ever come to that.' (N11) 1 Online tools (e.g. Meditech or HEALTHe NL) allow accessing the information which patients might not remember, and this will prevent unnecessary testing.
So, you know, we look up through our Meditech system or through the HEALTHe NL of visits that patients have made. Like we may ask a question "have you ever seen a cardiologist?" And some patients will say no, I've never seen anybody. And then you say well, you've seen such and such, maybe five years ago. Oh yeah, that's right. But sometimes they don't divulge that information.' (N11) And order sets and pre-existing written orders, routine-the bane of my life, the word "routine". There should be no such thing as a routine preoperative order because that's the problem is that people have become automated in it. And in fact, we changed some of our order sets to say that testing as per our policy and as per pre-anesthetic clinic nursing assessment.' (A7) 2

Timing and resources
If testing could be done closer to surgery, that would help us and patients (avoid follow-ups, travelling).
First of all, the screening questionnaire should not happen less than a week from the time of surgery so that you know whether there are any ongoing issues closer to the date of surgery.' (S3) did highlight environmental factors that make it more difficult for them to avoid routine ordering including a) a lack of access to technology and/or online tools (which makes it difficult for them to check past medical history of their patients and the results of any tests they have undergone), b) lack of staff and difficulty in accessing other specialists for consults (environmental context and resources).
2. HCPs believe that the positive effects of not ordering outweigh the negative and don't think the tests are likely to influence their practice but some still consider them a fail-safe-to ensure procedures move ahead as scheduled and that important clinical findings are not missed.
Most participants agreed the benefits of not ordering tests outweighed any potential risks (beliefs about consequences). Reported positive effects included reduced patient inconvenience, fewer false positives and unnecessary follow-up tests, less paperwork, reduced wait time for surgeries, and higher efficiency and cost-effectiveness (beliefs about consequences). They also stated that the results of the tests were unlikely to change their practice. Nevertheless, some participants noted that failing to order tests may result in surgery delays or cancellations or missing important clinical findings (beliefs about consequences).
3. There is a lack of clarity about who is responsible for deciding whether or not to order preoperative tests, though most agree that chest x-rays and ECGs are not required for low-risk patients.
There was significant confusion and conflicting comments among the participants with regards to responsibility for preoperative test-ordering (social/professional role and identity). The surgeons we interviewed reported that they have a different set of concerns and goals for surgery (compared to anaesthesiologists) and may therefore want to order different tests to prepare for surgery. They also reported that if they were unsure or concerned about a specific case, they would refer it to their anesthesiologist or internist colleagues for consultation (social influences). While both groups agreed that chest x-rays and ECGs for low-risk patients undergoing surgeries was not an expected part of preoperative assessments, it was not clear who was responsible for deciding whether or not to order these tests. Rather, we found that preoperative test-ordering (meant to support anesthesia management) was not at the sole discretion of the PAC or anaesthesiologists (social professional role and identity). Sometimes surgeons order these tests in an attempt to ward off potential cancellations or delays. In addition, participants reported that tests were sometimes ordered under surgeons' names by other HCPs without the surgeons' awareness. Consequently, the HCP ordering the test could not check the test results because they were sent to the surgeons who then became responsible for following up on the tests they had not ordered. A few participants also reported that sometimes surgeons' administrative staff would order tests on their behalf using order sets for all patients regardless of patients or surgery characteristics.
4. HCPs believe that implementing clearer guidelines, enhancing understanding of current evidence, and building consensus on a preoperative testing strategy, supported by improved communication and access to resources, and periodic evaluation will reduce unnecessary preoperative testing. Participants emphasised the importance of clearer guidelines, educating stakeholders on the current evidence, and ensuring that there is consensus among stakeholders regarding preoperative testing strategy to reduce routine preoperative testing (behavioral regulation). They also explained that endorsement of policies and guidelines by regulatory bodies could help reduce inappropriate test ordering. Several strategies were mentioned to help reduce test ordering: performing a thorough clinical history and physical exam, detailed documentation of patients' symptoms and reasons for testing/not testing, easy access to online tools (e.g., Meditech or HEALTHe NL), enabling pop-up questions when ordering a test (e.g., asking if patients' symptoms were new), and removing or changing order sets (behavioral regulation). Participants also suggested that audit and feedback on appropriateness of preoperative assessments and reminders about the benefits of not ordering could reduce test ordering. In terms of inter-professional relations, changing the accountability of test ordering and better communication with anaesthesiologists were highlighted. Table 2 presents a summary of the belief statements and supporting quotes for each of the four domains that were not considered relevant to preoperative test ordering: knowledge, skills, memory and decision making, and emotion. Most participants were aware of the preoperative guidelines and believed them to be evidence-based and trustworthy. A small number of participants were not sure about the details of the guidelines (knowledge). Almost all participants believed that basic clinical skills were enough for performing a history/physical exam and deciding whether tests were needed and that experience could improve the skills needed for preoperative assessments. They also felt that good interpersonal and communication skills with patients were important (skills). The decision to not order tests was an easy decision to make by most participants. However, as mentioned previously, some participants recognised that automaticity and environmental factors influenced their test ordering decisions and explained that they were mandated to automatically order tests according to policies set by hospitals, for example, if patients were a certain age (memory and decision processes). Almost all participants mentioned that not ordering tests did not worry them (emotion).

Discussion
This study used a theory-informed analysis to help understand the factors influencing lowvalue preoperative test-ordering by surgeons, anaesthesiologists, or preoperative clinic nurses in NL, Canada. We found that while HCPs may not intend to routinely order preoperative, in practice, a host of factors drive ordering decisions. Further, most participants believe that the benefits of not ordering outweigh potential risks, yet still order these tests in an attempt to ensure procedures move ahead as scheduled and that important clinical findings are not missed. Participants also reported a lack of clarity about who is responsible for deciding whether to order preoperative tests, though most agree that chest x-rays and ECGs are not required for low-risk patients. Respondents believe that implementing clear guidelines (at the institutional and/or health system level), enhancing understanding of current evidence, and building consensus on a preoperative testing strategy, supported by improved communication and access to resources, and periodic evaluation will reduce unnecessary preoperative testing.

Findings in relation to previous research
We found only three studies investigating why routine testing practices persist despite guidelines that advise otherwise. Two were very similar to our study parameters including interviews with surgeons, anesthesiologists, and/or nurse administrators (conducted in the US and Canada) [28] [34]. The third interviewed general surgeons involved in preoperative clinics in New Zealand [35].
Consistent with these studies, participants in our study agreed with guidelines recommending against low-value, routine preoperative test ordering and did not believe that these tests 'You have ways of getting information out of patients and the more patients you see the more experience you get, the better you should be at it.' (S1) 'I think coming out initially and inexperienced people, you're afraid to miss something so therefore you over-investigate, over-evaluate. And I think the time and expertise and that you see so many people, you get a better handle on them and you don't investigate as much'. (A8) 9

Required skill sets
A good skill set is to consider both patients' characteristics and the characteristics of the surgery/anesthesiology. 'You need to be able to do a comprehensive history and physical on the patient. You need to have a good understanding of what the surgery entails. Umm, and be able to specifically ask questions ah, on things that could affect the surgery. To find out if the patient has a possible comorbidity or a documented comorbidity that would hurt the outcome of the surgery.' (S16) 5 Good interpersonal and communication skills with patients are important to conducting an accurate assessment.
'I mean, you need to be able to complete an accurate history, which means you need to get the information out of the patient, and some people are easier to get that out of than others are. You have to be able to deal with the difficult communicator.' (S1) help or influence their practice [28,34]. Rather, they believe not ordering tests routinely can benefit patients (for example, by reducing patient discomfort and inconvenience) and the health system (for example, by reducing costs and improving efficiency) [28,34]. Additional practitioner-level barriers also noted in this study and the wider literature include the fear of missing "something serious" that could lead to adverse patient outcomes [34,35], medicolegal concerns, [34], worry that procedures will be cancelled or delayed if preoperative tests are not carried out [28,34], and beliefs about the preoperative testing needs and expectations of other specialties [28,34]. Further complicating the issue is confusion about professional responsibility (i.e., lack of clarity on who is responsible for ordering preoperative tests)-an issue also noted by Patey et al [28]. Our findings of systems-level drivers of routine testing were also reflected in the available literature. Brown & Brown (2011) and Raina et al. (2019) also found that practice traditions or workplace norms (e.g., routine testing strategies) were important barriers to reducing preoperative testing [34,35]. Additionally, Raina et al. (2019) also found that poor systems of communication between the HCPs and the departments involved, and a lack of staff or HCP time available for consults [35] are important barriers to change. These barriers, particularly poor communication between professions, is perhaps not surprising or unique to preoperative testing. Communication failures among teams of HCPs have been observed in many areas of healthcare resulting in redundancy, treatment errors, or even patient harms [36][37][38][39][40][41][42].
In contrast to other studies in this area [34,35], participants in this study were aware of preoperative testing guidelines and believed them to be evidence-based and trustworthy. This replicates findings from a Canadian study [28] which also didn't find that knowledge was a barrier to reducing preoperative testing and which had very similar study parameters and used a very similar interview guide. Guidelines recommending against routine preoperative testing strategies have been published for many years [43] and in recent years, Choosing Wisely has been actively campaigning on this issue which may partially explain why knowledge doesn't appear to be lacking among the participants we interviewed. Also, the questions about knowledge in the US [34] and the NZ [35] studies were focused on familiarity with the evidence around the benefits of preoperative testing, which guidelines were used in decision-making, and, in the NZ study, knowledge of the Choosing Wisely campaign. Globally, then, its not clear that knowledge is a major barrier but it does not appear to be the case in Canada.
Our participants also described additional contextual factors that drive routine testing including automatic order sets or pre-defined templates for preoperative evaluations, as well as lack of access to technology allowing for easy access to patient information. This issue was not initially included in our interview guide but came up in an early interview and was probed in subsequent interviews. This may be an issue relevant only in the local context, or it may not have surfaced previously simply because it was not asked about.
Finally, we found the desire to avoid interpersonal conflicts with colleagues also influenced physicians to order routinely. We believe this finding is related to other common barriers such as HCPs' beliefs about the needs and expectations of other HCPs and confusion about which HCPs are responsible for ordering. We were aware that previous studies had noted these types of issues so we knew to probe them if they came up in our own interviews resulting in a more nuanced understanding of this issue.

Strengths and limitations
As recommended by numerous health and research organizations, (e.g., the National Institute for Healthcare Excellence, the MRC, Health Canada, Canadian Institutes of Health Research, and the Quality Enhancement Research Initiative) [44][45][46][47][48], this study used a theory-guided investigation of the determinants of routine preoperative testing for low-risk surgeries. Using the Atkins et al guide [26] on how to apply the TDF to guide our assessment and analysis allowed us to produce results that can be used to develop a theory-informed intervention bestsuited to tackle known barriers to reducing routine testing. Additionally, we applied rigorous data collection and analysis methods (including a TDF-based question guide, extensive coder training, double coding of all transcripts, oversight of analysis by a professional expert in the TDF, and review of results interpretations with clinical experts and the investigative team. interviews until data saturation, double coding, coding to consensus, interpretation checked by experts and reviewed with team). We also published the study protocol which was reviewed by content experts in the TDF, qualitative research, and preoperative testing and used the Consolidated Criteria for Reporting Qualitative Research (COREQ) 32-item checklist to guide our methods and reporting [30].
Despite this, our results are limited in several ways. We were unable to interview participants working at all sites offering low-risk surgical procedures in the province as originally planned. However, we were able to include participants from all but one regional health authority. In addition, although we reached data saturation, it is possible that we did so prematurely by not interviewing participants with sufficient diversity to allow for more variety in responses. For example, while we were able to speak with HCPs in three of four provincial health regions, we did not interview providers working in Labrador who may face different barriers to reducing routine preoperative testing. Finally, we didn't assess the test-ordering practices of our sample to engage similar numbers of participants that order these tests at different rates; nor did we actively seek participants in equal numbers who had differing views on routine preoperative test-ordering.

Implications for research and practice
While HCPs interviewed for this study were aware of when to order preoperative tests according to guidelines, there are both system and practitioner-level barriers that continue to influence their practice. Many of these barriers occurred as a result of the complex nature of preoperative care and a lack of communication among providers suggesting that implementation is likely to be challenging. This challenge in implementing guidelines is further complicated when the health system fails to provide a clear set of guiding rules standardized for all professions, lack of communication with and "buy-in" from all professions involved in the patient's care, and lack of easy access to patient information. Based on these findings in NL, our next steps will be to select strategies for an intervention that can be trialled locally.
Clear endorsement of guidelines by health authorities/hospital administration and development of local policies about who is responsible for ordering tests which are clearly communicated to all surgical HCPs (surgeons, anesthetists, pre-admission clinic staff, and potentially GPs) could address most of the barriers we identified. This includes additional issues stemming from the "just in case" types of ordering which would likely be abated if the direction of the hospital is clear and if HCPs can support their decisions to not order tests using easy to access and up-to-date data from patients' medical records.
In the literature we found only three studies that have tried to reduce preoperative testing, all of which used strategies similar to what we have proposed above (two in the US [49,50] and one in Canada [51]) with the exception of clarifying responsibility for ordering. All interventions included some form of education for HCPs involved in ordering. In addition, two included decision support tools [49,51] and/or use of champions [50,51] to reinforce educational messages. While all studies showed promising results, certainty of the evidence is low. Trials in this area are long overdue. Recently, Ahmadi et al (2021) published a protocol for a randomized superiority trial planning to implement educational messages triggered by preoperative test ordering the EHR [52]. In Canada, a trial has been registered that aims to reduce preoperative testing for low-risk ambulatory procedures by improving accountability for ordering. They will do this by implementing a hospital policy directing preoperative tests to be ordered only by consulting anesthesiologists based on their clinical assessment of the patient undergoing surgery [53].